RE: [PATCH net] net: hns: Fix the device being used for dma mapping during TX

-----Original Message-----
From: YUAN Linyu [mailto:Linyu.Yuan@alcatel-sbell.com.cn]
Sent: Thursday, February 09, 2017 9:36 AM
To: Salil Mehta; davem@davemloft.net
Cc: Zhuangyuzeng (Yisen); mehta.salil.lnk@gmail.com;
netdev@vger.kernel.org; linux-kernel@vger.kernel.org; Linuxarm;
Yankejian (Hackim Yim)
Subject: RE: [PATCH net] net: hns: Fix the device being used for dma
mapping during TX

quoted

-----Original Message-----
From: netdev-owner@vger.kernel.org [mailto:netdev-

owner@vger.kernel.org]

quoted

On Behalf Of Salil Mehta
Sent: Thursday, February 09, 2017 5:24 PM
To: davem@davemloft.net
Cc: salil.mehta@huawei.com; yisen.zhuang@huawei.com;
mehta.salil.lnk@gmail.com; netdev@vger.kernel.org;
linux-kernel@vger.kernel.org; linuxarm@huawei.com; Kejian Yan
Subject: [PATCH net] net: hns: Fix the device being used for dma

mapping during

quoted

TX

From: Kejian Yan <redacted>

This patch fixes the device being used to DMA map skb->data.
Erroneous device assignment causes the crash when SMMU is enabled.
This happens during TX since buffer gets DMA mapped with device
correspondign to net_device and gets unmapped using the device
related to DSAF.

Signed-off-by: Kejian Yan <redacted>
Reviewed-by: Yisen Zhuang <redacted>
Signed-off-by: Salil Mehta <redacted>
---
 drivers/net/ethernet/hisilicon/hns/hns_enet.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/hisilicon/hns/hns_enet.c

b/drivers/net/ethernet/hisilicon/hns/hns_enet.c
index 672b646..2b52a12 100644

--- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c

@@ -305,7 +305,7 @@ int hns_nic_net_xmit_hw(struct net_device *ndev,
 			struct hns_nic_ring_data *ring_data)
 {
 	struct hns_nic_priv *priv = netdev_priv(ndev);
-	struct device *dev = priv->dev;
+	struct device *dev = ring_to_dev(ring_data->ring);
 	struct hnae_ring *ring = ring_data->ring;

struct device *dev = ring_to_dev(ring); ??????

Yes, name of the macro is slight misnomer but this gets the dsaf device.
Hope this answers your question?

Thanks
Salil

quoted

 	struct netdev_queue *dev_queue;
 	struct skb_frag_struct *frag;
--
1.7.9.5